The invention relates to an improved method for packaging a palletizable load, and in particular a method for automatically loading and strapping a load on a pallet. The invention also relates to the installation enabling the implementation of this method.
For a long time already, the transport of materials, both in bulk and in the form of primary packagings, such as packs, bottles, etc..., has been carried out by means of pallets on which the primary packagings are held by fixing means such as heat-shrink wrappings or by wrapping using a tape, this latter technique being known as "strapping". In fact, there is an increasing demand to minimize the time necessary for the loading and strapping of these pallets, when this technique is implemented, while at the same time increasing their capacity for resisting the various shocks which they may be subjected to during the transport and various handling operations which they undergo.
As regards minimizing the loading times, palletization robots are already known which automatically position the articles to be loaded from a conveyor, while memorizing the various positions which may be filled on the pallet, and the level of the loading taking place.
In addition, in order to provide a greater cohesion for the loads palletized in this way, it is known, particularly with bags of bulk materials for example, to partially coat these bags by means of a socalled "palletization" glue, having the property of not drying completely, thus enabling the articles of intermediate levels to be glued together. Nevertheless, this placing of glue does not prove to be satisfactory, since it generally turns out to be difficult to get rid of all the glue, and as a result of this, it causes dirtiness.
It has then been proposed to insert intermediate sheets made of cardboard or plastic between the various palletization levels. Even though these sheets provide the general cohesion of the load of the articles of a same layer or of a same level of palletization, they do not prevent, on the other hand, the slipping of a complete layer relative to the preceding or following layer and it is only after placing of the stretchable plastic film for strapping or of the heat-shrink wrapping that the cohesion of the assembly of the primary packagings on the pallet is obtained.
Even though these solutions are satisfactory as regards technique and automation, they have the crippling disadvantage of using plastic films which are not naturally degradable, and which therefore cause pollution.
Consequently, one object of the invention is to propose a method for packaging a palletizable load which, on the one hand, avoids the disadvantages inherent in plastic films implemented in the known techniques, while on the other hand, providing an excellent cohesion of the palletized loads.